/**
 * Copyright (C) 2002-2015   The FreeCol Team
 * <p>
 * This file is part of FreeCol.
 * <p>
 * FreeCol is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 2 of the License, or
 * (at your option) any later version.
 * <p>
 * FreeCol is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * <p>
 * You should have received a copy of the GNU General Public License
 * along with FreeCol.  If not, see <http://www.gnu.org/licenses/>.
 */

package net.sf.freecol.common.networking;

import net.sf.freecol.common.model.Game;
import net.sf.freecol.common.model.Player;
import net.sf.freecol.common.model.StringTemplate;
import net.sf.freecol.server.FreeColServer;
import net.sf.freecol.server.model.ServerPlayer;

import org.w3c.dom.Element;


/**
 * The message sent when a player declares independence.
 */
public class DeclareIndependenceMessage extends DOMMessage
{

    /** The new name for the rebelling nation. */
    private final String nationName;

    /** The new name for the rebelling country */
    private final String countryName;


    /**
     * Create a new <code>DeclareIndependenceMessage</code> with the
     * supplied name.
     *
     * @param nationName The new name for the rebelling nation.
     * @param countryName The new name for the rebelling country.
     */
    public DeclareIndependenceMessage( String nationName, String countryName )
    {
        super( getXMLElementTagName( ) );

        this.nationName = nationName;
        this.countryName = countryName;
    }

    /**
     * Create a new <code>DeclareIndependenceMessage</code> from a
     * supplied element.
     *
     * @param game The <code>Game</code> this message belongs to.
     * @param element The <code>Element</code> to use to create the message.
     */
    public DeclareIndependenceMessage( Game game, Element element )
    {
        super( getXMLElementTagName( ) );

        this.nationName = element.getAttribute( "nationName" );
        this.countryName = element.getAttribute( "countryName" );
    }


    /**
     * Handle a "declareIndependence"-message.
     *
     * @param server The <code>FreeColServer</code> handling the message.
     * @param player The <code>Player</code> the message applies to.
     * @param connection The <code>Connection</code> the message is from.
     *
     * @return An update <code>Element</code> describing the REF and the
     *         rebel player, or an error <code>Element</code> on failure.
     */
    public Element handle( FreeColServer server, Player player,
                           Connection connection )
    {
        final ServerPlayer serverPlayer = server.getPlayer( connection );

        if ( nationName == null || nationName.isEmpty( )
                || countryName == null || countryName.isEmpty( ) )
        {
            return DOMMessage.clientError( "Empty nation or country name." );
        }
        StringTemplate problem = player.checkDeclareIndependence( );
        if ( problem != null )
        {
            return DOMMessage.clientError( "Declaration blocked" );
        }

        // Declare.
        return server.getInGameController( )
                .declareIndependence( serverPlayer, nationName, countryName );
    }

    /**
     * Convert this DeclareIndependenceMessage to XML.
     *
     * @return The XML representation of this message.
     */
    @Override
    public Element toXMLElement( )
    {
        return createMessage( getXMLElementTagName( ),
                              "nationName", nationName,
                              "countryName", countryName );
    }

    /**
     * The tag name of the root element representing this object.
     *
     * @return "declareIndependence".
     */
    public static String getXMLElementTagName( )
    {
        return "declareIndependence";
    }
}
